Yeah, so I imagine lots of people have heard about the US letting a guy with a bloody chainsaw, among other weapons, into the country and then finding out he murdered two people?  Google Gregory Despres, or here is a link from the BBC. 

FYI, that’s the border I’ve crossed most often.  On more than one occasion, whilst driving a CAR through the checkpoint late at night, I’ve had to honk to wake up the — I swear to god — sleeping customs agent to get cleared through.  There’s no gate, I assume there’s an alarm if I just drove through, but yeah.  Whooohooo, Maine is famous again. Sigh.